1. Field of the Invention
This invention relates to a device for measuring the contour length of a two-dimensional pattern.
2. Description of the Prior Art
Measurement of the length of the contour (to be referred to in this specification as "contour length") of a two-dimensional pattern is required in various fields. In general, it has been known that the contour length of a pattern is largely dependent not only upon the size of the pattern, but also upon the complexity of the pattern itself. There has already been devised and demonstrated a method for measuring the contour length of a pattern wherein the pattern is converted or encoded into a digitally coded pattern consisting of binary digits 0's and 1's, and the contour length is measured based upon the assumption that the number of picture elements including the boundary line of the pattern is in proportion to the contour length.
There has also been proposed another method for making contour length measurements in which the contour or boundary line is approximated by a large number of polygons.
In both of the foregoing methods, the continuous contour or boundary line is approximated by the digital or discrete line segments or patterns so that accurate measurement of the contour length is impossible.